DESCRIPTION: (Adapted from the applicant's narrative) The Biochemical Core laboratory performs routine biochemical analyses in a more efficient and cost effective manner than having the samples analyzed in commercial or hospital based labs. The centralized Biochemical Core facility also ensures uniformity of assay results, maintains complete, centralized records and well defined quality control guidelines for each assay. The core will (1) establish and ensure uniform methods for the collection, labeling, storage, and transport of samples; (2) provide reliable, reproducible, uniform and timely analyses of urine, plasma and tissue samples for the project investigators; (3) maintain hard copy records and to enter the results for all biochemical and hormone measurements on electronic spreadsheet; (4) oversee and maintain shared use equipment in the core that is utilized by project investigators and train personnel of project investigator's laboratories in the proper use of the equipment; and (5) provide expertise and equipment to assist investigators in developing new assays as needed. (End of Abstract) This core facility will provide and ensure uniform collection of samples, reliable analyses, maintenance of records, maintenance of shared equipment, and development of new assays. In the past 4 years of the project, 26,568 samples have been collected and analyzed from over 400 patients and 650 rats. Human samples have been analyzed in 18 different assays while rats samples have been analyzed in 11 different assays. In addition to the traditional biochemical assays (glucose, lipids, creatinine, electrolytes, etc.), radioimmunoassays and HPLC measurements were made (catecholamines, renin, aldosterone, insulin, vasopressin). New assays were also developed during the funding period including a new extraction method for ANF from human samples, examination of the rate of cryoactivation of African American vs. French Canadian plasma to look for the large differences seen in plasma renin activities, development of a leptin assay, a new EIA for urinary albumin, and conversion of RIA's for cGMP and cAMP to higher throughput microtiter plate EIA's. It is anticipated that in the coming project years 53,050 samples will be presented to the laboratory. This is an important component of this program. It is extremely well organized and well equipped. The personnel are very capable, and it will serve the program well.